This invention relates to a safety appliance releasably attachable to an upright safety cable and adapted to clamp upon the cable to prevent falling of a workman climbing an elevated structure, and in particular to a safety clamp which is operable with or without spring loading.
Although cable safety clamp appliances have been known heretofore, it has been found that in many applications of such appliances on safety cables, there often is a need for a plurality of such devices on a cable so that a number of workmen may utilize the same safety cable in climbing to elevated positions. This often requires the connecting or disconnecting of safety clamp appliances on the safety cable depending on the number of workmen. There are also occasions where a safety clamp appliance needs to be spring loaded in order to maintain constant gripping of the safety cable as in the case of industrial workers. Other occasions require a safety clamp appliance which is easily slidable along the safety cable and, therefore, the safety clamp appliance should not be spring loaded. (Such occasions occur in mountain climbing and cave exploration.)
Prior safety clamp appliances are either spring loaded or not spring loaded. The prior art does not disclose a clamp which may be used either as a spring loaded appliance or as a non-spring loaded appliance.
A search of the prior art patents developed a number of patents which are spring loaded, these include the following:
U.S. Pat. No. 1,250,876 Hicks PA1 U.S. Pat. No. 3,179,994 Meyer et. al. PA1 U.S. Pat. No. 3,364,529 Blacher PA1 U.S. Pat. No. 3,852,943 Healy PA1 U.S. Pat. No. 4,077,094 Swager
Each of the above listed patents shows a clamping safety appliance with a torsion spring contact with the safety cable. The torsion spring is fixed to the appliance in such a way that it would be difficult to remove to convert the safety clamp appliance from spring loaded to non-spring loaded. The need for a single clamp appliance which may be used in a spring loaded mode or a non-spring loaded mode would be very useful in industrial applications and in mountain climbing or cave exploration, particularly in terms of savings in time and money.